/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright (c) 1997-2012 Oracle and/or its affiliates. All rights reserved.
 *
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://github.com/payara/Payara/blob/main/LICENSE.txt
 * See the License for the specific
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 * file and include the License file at legal/OPEN-SOURCE-LICENSE.txt.
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// Portions Copyright [2019] Payara Foundation and/or affiliates

package org.glassfish.admin.amx.util;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

/**
The API that should be used to output from a Cmd running within the framework.
 */
public final class FileUtils
{
    private FileUtils()
    {
    }

    public static String fileToString(final File src) throws FileNotFoundException, IOException {
        return fileToString(src, 32 * 1024);
    }

    public static String fileToString(final File src, final int readBufferSize) throws FileNotFoundException, IOException {
        final long length = src.length();
        if (length > 1024 * 1024 * 1024)
        {
            throw new IllegalArgumentException();
        }

        final char[] readBuffer = new char[readBufferSize];

        final StringBuilder result = new StringBuilder((int) length);
        try (FileReader in = new FileReader(src)) {
            while (true)
            {
                final int numRead = in.read(readBuffer, 0, readBufferSize);
                if (numRead < 0)
                {
                    break;
                }

                result.append(readBuffer, 0, numRead);
            }
        }

        return (result.toString());
    }

    public static void stringToFile(final String s, final File dest) throws IOException {
        try (FileWriter out = new FileWriter(dest)) {
            out.write(s);
        }
    }

}
